RL78/F13, F14 CHAPTER 14 COMPARATOR (RL78/F14 Only)
R01UH0368EJ0210 Rev.2.10 786
Dec 10, 2015
14.2.8 Port mode register (PM8)
When using the P81/ANI3/IVCMP00, P82/ANI4/IVCMP01, P83/ANI5/IVCMP02, P84/ANI6/IVCMP03, or
P85/ANI7/IVREF0 pin for an analog input port of the comparator, set the PM81, PM82, PM84, or PM85 bit to 1
corresponding to the port to be used.
If the PM81 to PM85 bits are set to 0, they cannot be used as analog input port pins.
The PM8 register can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation sets these registers to FFH.
Caution If a pin is set as an analog input port, not the pin level but “0” is always read.
Figure 14-9. Format of Port Mode Register 8 (PM8)
Address: FFF28H After reset: FFH
Symbol 7 6 5 4 3 2 1 0
PM8 PM87 PM86 PM85 PM84 PM83 PM82 PM81 PM80
PM8n P8n pin input/output mode selection (n = 0 to 7) R/W
0 0: Output mode (output buffer on) R/W
1 1: Input mode (output buffer off)
The P81/ANI3/IVCMP00, P82/ANI4/IVCMP01, P83/ANI5/IVCMP02, P84/ANI6/IVCMP03, and P85/ANI7/IVREF0 pins
are as shown below depending on the settings of the A/D port configuration register (ADPC), analog input channel
specification register (ADS), and PM8 registers.
Table 14-4. Setting Functions of P81/ANI3/IVCMP00 to P85/ANI7/IVREF0 Pins
ADPC Register PM8 Register ADS Register P81/ANI3/IVCMP00 to P85/ANI7/IVREF0
Digital I/O selection Input mode
Digital input
Output mode
Digital output
Analog I/O selection Input mode Selects ANI. Analog input (to be converted)
Does not select ANI. Analog input (not to be converted)
Output mode Selects ANI. Setting prohibited
Does not select ANI.
Reset signal generation sets all the P81/ANI3/IVCMP00 to P85/ANI7/IVREF0 pins to analog input.
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